1. Field of the Invention
The present invention relates generally to substrate preparation, cleaning, and drying and, more particularly, to systems, apparatus, and methods for improving semiconductor substrate preparation, cleaning, and/or drying by reducing preparation time and cost associated with substrate preparation operations.
2. Description of the Related Art
The fabrication of semiconductor devices involves numerous processing operations. These operations include, for example, dopant implants, gate oxide generation, inter-metal oxide depositions, metallization depositions, photolithography patterning, etching operations, chemical mechanical polishing (CMP), etc. As these operations generate particles and residues, substrate surfaces need to be cleaned so as to remove particulate contaminants adhered to the surfaces of the substrate.
Particulate contaminants generally consist of tiny bits of distinctly defined material having an affinity to adhere to the surfaces of the substrate. Examples of particulate contaminants can include organic and inorganic residues, such as silicon dust, silica, slurry residue, polymeric residue, metal flakes, atmospheric dust, plastic particles, and silicate particles, among others. Particulate contaminants should be removed from substrate surfaces as leaving behind such contaminants on substrate surface can have detrimental effects on the performance of integrated circuit devices.
Cleaning the substrate front sides (i.e., the active side or top surface) has traditionally been given a higher priority in typical substrate cleaning systems and processes because deleterious defects may be caused in the processing of the substrates. However, as substrate sizes have increased and/or feature sizes have decreased, certain shortcomings have been associated with the failure to adequately and properly clean and process substrate backsides (i.e., non-active side).
One drawback of having contaminant particulates on substrate backsides is migration of particulate contaminants from the substrate backside to the substrate front side. For example, the migration may occur during a wet processing step and/or as the substrate is being moved or otherwise handled between the processing or metrology tools. Furthermore, the backside contaminants can undesirably migrate from one process tools or steps thus contaminating subsequent processes.
To eliminate such drawbacks, in certain substrate processing operations, the substrate front side and backside are cleaned in a cleaning apparatus using chemicals. Thereafter, to produce a low defect level substrate, the substrate backside and front side are rinsed by, for example, De Ionized (DI) water. In this manner, the chemicals remaining on the substrate front side and backside are diluted and/or residual particulate contaminants thereon are displaced. Producing a substrate with low-defect level, however, can require that the substrate front side and backside be rinsed sufficiently. That is, the substrate front side and backside can be rinsed using a large amount of DI water for a specific period of time, which often, can be as long as the time spent to clean and/or process the substrate front side and backside. Of course, cleaning and/or processing the substrate surface may take an extended amount of time.
Additionally, in certain scenarios, certain conditions of the substrate front side (e.g., a portion of the device being expose, etc.) wherein rinsing the substrate front side may adversely affect the condition of the substrate surface. For instance, rinsing silicon substrate may result in re-growing of oxide on the exposed portions of the substrate surface while, in a copper substrate, rinsing the substrate front side and backside may result in corrosion.
In view of the foregoing, there is a need for a system, apparatus, and method for preparing substrate surfaces capable of substantially reducing the time and cost associated with processing the front side and backside of substrates.